Method of making a sheathed soft-feel handle

ABSTRACT

A method of efficiently making a soft-feel handgrip for a handle construction wherein a relatively smooth strip of metal is placed against one face of a cushioning member and wrapped in a thermoplastic sheath, open at least at one of its transverse ends and having longitudinal ends which overlap against the metal strip. The metal strip is operatively connected to a grounded bed, a die placed against the longitudinal overlapped end of the sheath and a high frequency alternating current is applied between the die and bed to seal the overlapped longitudinal ends dielectrically, after which the metal strip is removed from the open end of the sheath and the latter closed off by clamping, sealing or adhesion to complete the handgrip.

United States Patent Szabo July 1, 1975 [54] METHOD OF MAKING A SHEATHED SOFT-FEEL HANDLE Primary ExaminerD0uglas J. Drummond [75] Inventor: Marton J. Szabo, Camden, NJ. Attorney Agent or Firm-Max Mmman [73] Assignee: P.H.C. Industries, Inc., Camden, [57] ABSTRACT A method of efficiently making a soft-feel handgrip [22] pfled; July 29 1974 for a handle construction wherein a relatively smooth Appl. No: 492,711

strip of metal is placed against one face of a cushioning member and wrapped in a thermoplastic sheath. open at least at one of its transverse ends and having longitudinal ends which overlap against the metal strip. The metal strip is operatively connected to a grounded bed, a die placed against the longitudinal overlapped end of the sheath and a high frequency alternating current is applied between the die and bed to seal the overlapped longitudinal ends dielectrically, after which the metal strip is removed from the open end of the sheath and the latter closed off by clamp ing, sealing or adhesion to complete the handgrip.

6 Claims, 6 Drawing Figures METHOD OF MAKING A SHEATHED SOFT-FEEL HANDLE This is an improvement over my US. Pat. No. 3.758.360 and its parent U.S. Pat. No. 3.736.62l.

ln said patents a method of making a soft-feel handgrip for a handle construction is disclosed in which a flexible electrically conductive member is placed against one face of a cushioning member. a thermoplastic sheath is made to encompass said members with overlapping longitudinal ends directly over the conductive member. the sheathed unit is placed on a conductive grounded bed with one end of the flexible conductive member operatively connected thereto. a die is placed against the overlapped ends of the sheath and a high frequency alternating current is applied between the bed and the die to seal the overlapped ends dielectrically. The resultant handgrip includes the flexible electrically conductive member.

In order for the handle to retain its soft feel. it is preferred that the flexible conductive member be metal foil. a conductive adhesive strip. a coating of metal on a face of the cushioning member. etc.

Applicant has now found that it can make. and it is the primary object of the invention to make. a soft-feel handle using the method disclosed in said patents as described hereinbefore. but without the need to retain the flexible conductive strip in the final construction of the handle. yet obtain all of the benefits of said method of obtaining efficient sealing of the lap seam of the ther moplastic sheath using high frequency alternating current. Thus. the need to make the electrically conductive strip of metal foil. a conductive adhesive or metal coating on the cushioning material of such resiliency as to follow the shape of the handle. is eliminated in the event that these materials are in short supply or too ex pensive.

Another object of the invention is to provide a method of making a soft-feel sheathed handgrip using an electrically conductive member against one face of a cushioning member which can be readily removed after the lap seam is sealed dielectrically. which conductive member can be reused over and over again in the process of sealing.

Another object of the invention is to provide a method of the character described in which the cashioning member is compressed during the sealing process and when the conductive member is slid out of one end of the handgrip. the cushioning member will eit pand and fill the space previously occupied by the conductive member.

Yet another object of the invention is to provide a method ofthe character described in which the sheath.

conductive and cushioning members contain relatively smooth contacting surfaces so as to minimize friction between them and allow the conductive member to he slid out of one open end of the handgrip after the lap seam is sealed with case. after which the open ends of the handgrip may be closed off by the use of sealing. adhesion or a pinch collar.

These and other objects of the invention will become more apparent as the following description proceeds in conjunction with the accompanying drawings. wherein:

llfi. l is a diagrammatic view of a conventional dielectric scaling machine with the handgrip of the in stunt invention in place ready for the sealing operation and partly in section.

FIG. 2 is a sectional view taken on the line 2-2 of FIG. 1'.

FIG. 3 is a perspective view ofthe handle illustrating the removal of the conductive member after sealing of the lapped ends of the sheath;

FIG. 4 is a sectional view taken on the line 44 of FIG. 3;

FIG. 5 is a view similar to FIG. 4 of a modified form of the invention without a spring steel core; and

FIG. 6 is an elevational view of one type of handle made in accordance with the invention.

Specific reference is now made to the drawings in which similar reference characters are used for corresponding elements throughout.

Considering first the handle construction 10 shown in FIGS. 1-4. the grip portion 12 thereof comprises a core of flat spring bar 14. generally about one sixty-fourth inch to one thirtysecond inch thick. :1 filler strip l6. generally about three thirty-seconds inch thick. a pair of upper and lower cushioning strips 18 and 19 generally about one-sixteenth to three-eighths inch thick and a sheath or cover 20. generally about one thirty-second inch thick.

The core 14 may be made of any suitable spring metal. preferably steel. The filler strip 16. either on one or both sides of the spring steel. may be made of paper impregnated with rubber. cotton duck. cardboard. leather and the like. The cushioning strips 18 and 19 may be made of any suitable flexibly resilient material such as foam polyurethane. polystyrene. polyester and rubber. The sheath or cover 20 may be made of any suitable thermoplastic resin such as polyvinyl chloride. polystyrene. polycarbonate. polyurethane. the acrylics. etc.. in single ply or two ply such as \inyl bonded to a vegetable fiber. which generally has a relatively smooth interior face 2].

The spring metal core. filler strip and cushioning strips are secured at their interfaces with suitable adhesive as may be the upper face 22 of the upper cushioning strip 18. The opposite or lower face of the sheath. i.e. the finger-engaging portion. comprises longitudinally overlapping free edges 24 and 26.

lnterposed directly between the overlapped edges 24. 26 of the sheath and the lower cushioning strip 19 is an electrically conductive member 27. The member 27 is a relatively thin elongated piece of metal. preferably about 0.002 inch thick. with relatively smooth upper and lower surfaces 28. The member 27 must not be so thin as to create too much resistance to the flow ofcnr rent therethrough.

The outer surfaces of the cushioning strips especially the upper surface of the cushioning strip l9 beneath the conductive member 27 should also be relatively smooth.

As seen in FlGS. l and 3. the cushioning strips 18 and 19 and tilier in are comtensive with the sheath 20. but the sheath is open at both of its ends as at 2) and the conductive member 27 and spring steel core l4 extend through the open ends 29 of the handgrip.

A conventional dielectric scaling apparatus having a fixed bed 30 connected to ground. a vertically movable die or electrode 32 substantially coextensive with the handgrip l0 and a wry high frequency alternating current connected therebetween is employed. See. for example. Heat Sealing" by Robert D. Farkas. Reinhold Publishing Corporation. New York. I964. chapters 7 and 8. which is herein incorporated by reference. The

handgrip with the spring core 14 and conductive strip 27 extending beyond the ends of the sheath or cover is laid in a well in the bed with the overlapping ends 24 and 26 facing the die 32. A metal clamp 34 engages the free ends ofthe conductive strip and core and conductively connects them to the bed. While only one such clamp is shown on the right hand side in FIG. I, it will be understood that usually another such clamp is provided on the left hand side of the bed and engages the free ends ofthe core and the conductive strip in the same manner. although a single clamp is operative.

When the die is lowered into the contact with the overlapping ends 24 and 26 of the sheath or cover 20 and the current is applied. the overlapped ends become sealed as shown in FIGS. 2 and 4. It has been found that with a construction such as that described hereinbefore using a dielectric sealing machine with a 2 kw. output. the sheath can be effectively sealed in about 4 seconds. Also. when the die 32 contacts the overlapping longi' tudinal ends of the sheath the cushioning material. particularly the strip [9, is compressed somewhat.

Thereafter. the conductive strip or member 27 is pulled out of one of the open ends 29 of the handgrip in the direction of the arrow in FIG. 3 until it is entirely removed whereupon the somewhat compressed cushioning material expands to fill in the space previously occupied by the strip 27. Because the surface 28 of the conductive strip is relatively smooth as are the top surface of cushioning material 19 and the inner surface of the sheath 20. the slide removal action of the conduc tive strip is easily accomplished. The resultant handgrip in cross-section without the conductive strip 27 is shown in FIG. 4. The conductive strip 27 can of course be reused.

Although a handgrip construction with a core of spring metal is preferred. a handgrip construction without such a spring metal core may also be made by the method of the invention. Such a construction is shown in FIG. 5 and comprises essentially a pair of upper and lower cushioning strips 36 and 38 separated by a filler strip 40 and a thermoplastic sheath or cover 42 encompassing these members. the lower face of the sheath having overlapped ends 44 and 46. as in the construction shown in FIG. 4. The contacting surfaces of the members 36. 38 and 40 may be secured to each other by adhesion. The filler strip 40 may be thicker or otherwise made more rigid than those employed with the metal core of FIGS. 1-4 to stiffen the handgrip yet permit it to be flexible.

After the overlapped longitudinal ends 24 and 26 have been dielectrically sealed and the conductive strip 27 withdrawn. the open ends 29 of the handgrip assembly are closed by any suitable means as by overlapping the transverse ends of the sheath and securing them by sealing or adhesion or. if the spring metal core [4 is used. as seen in HO. 6. metal collars 48 are crimped as at 50 around the overlapped transverse ends 52 of the sheath and to the spring metal core 14 and various types of hardware or adapters can be secured to the ends ofthe handgrip so as to effect pivotal. slide or similar connections of the handle to the wall of a carrying case or the like.

While preferred embodiments of the invention have here been shown and described. it will be understood that minor variations may be made without departing from the spirit of the invention and the scope of the appended claims.

What is claimed is:

l. A method of making an elongated soft-feel hand grip for a handle construction comprised of placing an electrically conductive member against one face of a cushioning member. encompassing said members in a thermoplastic sheath which is coextensive with said cushioning member so that its longitudinal free ends overlap directly on said conductive member. said sheath being open at least at one of its ends with said conductive member extending therethrough. placing the sheathed unit on a conductive grounded bed and operatively connecting the extended end of said conductive member thereto. placing a die against said overlapped ends of said sheath. applying a high frequency alternating current between the die and bed for a time sufficient to seal said overlapped ends of said sheath dielectrically, said die acting to compress said cushioning member during the sealing operation and removing said conductive member through said one open end of said sheath after said overlapped longitudinal ends of said sheath have been sealed. said cushioning member expanding to occupy the space left by the removal of said conductive member to provide a tight soft-feel handle.

2. The method of claim I wherein the contacting surfaces of said sheath. cushioning member and conductive member therebetween are relatively smooth so that said conductive member can be readily slid out of said one open end of said sheath after the overlapped longitudinal ends thereof have been sealed.

3. The method of claim I and interposing a stiffening member between a pair of cushioning members prior to encompassing the same in said sheath.

4. The method of claim 2 wherein said stiffening member is a spring metal bar at least one end of which extends beyond said sheath and is operatively connected with said extended end of said conductive member to the conductive grounded bed.

5. The method of claim 1 wherein said conductive member is a strip of metal.

6. The method of claim I and closing off said open end of said sheath after removal of the conductive member. 

1. A METHOD OF MAKING AN ELONGATED SOFT-FEEL HANDGRIP FOR A HANDLE CONSTRUCTION COMPRISED OF PLACING AN ELECTRICALLY CONDUCTIVE MEMBER AGAINST ONE FACE OF A CUSHIONING MEMBER ENCOMPASSING SAID MEMBERS IN A THERMOPLASTIC SHEATH WHICH IS COEXTENSIVE WITH SAID CUSHIONING MEMBER SO THAT ITS LONGITUDINAL FREE ENDS OVERLAP DIRECTLY ON SAID CONDUCTIVE MEMBER, SAID SHEATH BEING OPEN AT LEAST AT ONE OF ITS ENDS WITH SAID CONDUCTIVE MEMBER EXTENDING THERETHROUGH, PLACING THE SHEATHED UNIT ON A CONDUCTIVE GROUNDED BED AND OPERATIVELY CONNECTING THE EXTENDED END OF SAID CONDUCTIVE MEMBER THERETO, PLACING A DIE AGAINST SAID OVERLAPPED ENDS OF SAID SHEATH, APPLYING A HIGH FREQUENCY ALTERNATING CURRENT BETWEEN THE DIE AND BED FOR A TIME SUFFICIENT TO SEAL SAID OVERLAPPED ENDS OF SAID SHEATH DIELECTRICALLY, SAID DIE ACTING TO COMPRESS SAID CUSHIONING MEMBER DURING THE SEALING OPERATION AND REMOVING SAID CONDUCTIVE MEMBER THROUGH SAID ONE OPEN END OF SAID SHEATH AFTER SAID OVERLAPPED LONGITUDINAL ENDS OF SAID SHEATH HAVE BEEN SEALED, SAID CUSHIONING MEMBER EXPANDING TO OCCUPY THE SPACE LEFT BY THE REMOVAL OF SAID CONDUCTIVE MEMBER TO PROVIDE A TIGHT SOFT-FEEL HANDLE.
 2. The method of claim 1 wherein the contacting surfaces of said sheath, cushioning member and conductive member therebetween are relatively smooth so that said conductive member can be readily slid out of said one open end of said sheath after the overlapped longitudinal ends thereof have been sealed.
 3. The method of claim 1 and interposing a stiffening member between a pair of cushioning members prior to encompassing the same in said sheath.
 4. The method of claim 2 wherein said stiffening member is a spring metal bar at least one end of which extends beyond said sheath and is operatively connected with said extended end of said conductive member to the conductive grounded bed.
 5. The method of claim 1 wherein said conductive member is a strip of metal.
 6. The method of claim 1 and closing off said open end of said sheath after removal of the conductive member. 